This invention relates to a method for creating marking lines comprising a plurality of elements and comprising a highly viscous marking material on a surface that is to be marked, especially a road surface, with pressurized marking material being discharged through an outlet that can be opened and closed while being moved relative to the surface. Moreover, the invention relates to a device for creating marking lines comprising a plurality of elements and comprising of a highly viscous marking material on a surface that is to be marked, especially a road surface; by means of the device, pressurized marking material can be discharged through an outlet that can be opened and closed while being moved relative to the surface.
For the creation of such markings, the methods and devices according to the documents DK 166 378 and PCT/DK 98/00446 have so far become known.
In both known methods, the material emerges as a continuous strip from a slot whose width corresponds to the width of the marking line, and said material is separated by a rotating cutting and ejecting device with paddles or vanes and ejected onto the road surface.
A disadvantage of these methods presents the wetting of the cutting and ejecting device rotating outside of the housing holding the material and having the outlet slot. Marking material will not only be ejected on the desired places of the road surface but, depending on the speed and depending on the material collecting on the ejecting device, also in portions of uncontrolled size in other radial directions as well. There is accordingly a major influence of moving speed and thus also the rotary speed of the ejecting device. One part of this material ejected in an uncontrolled manner actually does get onto the road surface, but not at the desired places. Another part of the uncontrolled ejected material which is not desired on the road surface must be trapped by spray protection devices in which the trapped material will collect in turn. This will result in regular interruptions of the work to free spray protection devices from the material collected there. For material to be processed hot and solidifying when cooling, there will be additional problems due to material solidifying on the ejecting and spray protection devices when these devices are not heated which is expensive and problematic.
Another problem presents the creation of exact ends of the marking lines. Although the material discharge from the housing can be abruptly started and ended by abruptly opening and closing the discharge slot; yet, with the known devices, material collected on the cutting and ejecting device will still continue to be ejected, over a longer distance, in an uncontrolled manner and only gradually abating. Additionally, over a longer distance, material collected on the spray protection devices will drip which also results in undesirable “contaminations” in the breaks of the marking lines. A successful prevention of these undesirable material applications in the marking line breaks will require complex measures, e.g. providing collection pans underneath.
From DE 43 27 701 C2, a method is known for the application of a highly viscous marking material in several layers parallel with each other on a stationary surface. Moreover, this document describes an application device for the implementation of the method. This method provides that each of the layers is applied pre-selectably in one of two different thicknesses. In the device for the implementation of this method, several closing elements are arranged side by side on its discharge side, the elements being movable independently from each other between a closing position and an adjustable opening position, in which the corresponding closure element releases a discharge slot of a predetermined width, with each of the closing elements being movable independently from the others into a second opening position in which one discharge slot is provided with a second pre-definable width. According to this method and the pertinent device, marking lines can be created which have, area-specifically, different thicknesses, in longitudinal direction of the marking lines as well as in a transverse direction thereto. The closing elements of the device have three operating conditions, i.e. “closed”, “smaller width” and “larger width”. The closing elements between these three positions are reset pneumatically or hydraulically without intermediate positions being assumed for any appreciable periods of time. The marking lines thus created have a very regular pattern which usually consists of a full-area basic layer and of rectangular surfaces which are elevated relative thereto. This method and the pertinent device are not suitable for creating marking lines comprising a plurality of especially droplet-shaped elements.